Divinylarene dioxide, such as divinylbenzene dioxide (DVBDO), an oxirane compound, advantageously can have a 1,000 times lower viscosity (for example, 8 mPa-s-12 mPa-s) than conventional epoxy resin compounds; and divinylarene dioxide resins are beneficially used in many applications including for example coatings, laminates and adhesives. Therefore, it would advance the art to provide a process for preparing an oxirane compound at high yields and high selectivity on a commercial scale.
Currently known processes for producing an oxirane compound include a batch, a semi-batch process or a continuous process. Known batch or a semi-batch process for producing a divinylarene dioxide resin, such as DVBDO, have the disadvantage of, for example, involving highly exothermic oxidation of divinyl benzene (DVB) with a net heat of reaction of up to 606 kJ/mol and an adiabatic temperature rise up to 523 K for a feed stream composition containing up to 13 weight percent (wt %) DVB. The reaction exotherm of the semi-batch process, for example, is addressed by slow addition of the reactants over 4-5 hours resulting in a long processing time of up to 6 hours; and hence, the productivity of the process is considered low. For example, the yield of DVBDO produced in a 15.14 cubic meter batch reactor is about 150 kg/hour.
U.S. Pat. No. 2,977,374 discloses a continuous process for preparing oxirane compounds; and the advantages of a continuous process over a batch synthesis. WO/2012/082482 and WO 2011/084687 A1 disclose a process to make divinylarene dioxide from divinyl benzene in the presence of a peroxycarboximidic acid agent. WO/2012/082482 mentions using a process including a combination of a continuous stirred tank reactor (CSTR) and a plug flow reactor (PFR) for continuously processing divinylbenzene dioxide.